More powerful match criteria for fragments

docs/kittens/hyperlinked_grep.rst

@@ -14,13 +14,12 @@ following contents:
     # Open any file with a fragment in vim, fragments are generated
     # by the hyperlink_grep kitten and nothing else so far.
     protocol file
-    has_fragment yes
+    fragment_matches [0-9]+
     action launch --type=overlay vim +${FRAGMENT} ${FILE_PATH}
 
     # Open text files without fragments in the editor
     protocol file
     mime text/*
-    has_fragment no
     action launch --type=overlay ${EDITOR} ${FILE_PATH}